Alien Biology: What Are Little Aliens Made Of?

Sean here again. Before we talk about the biology of life from other planets, it’s helpful to know a little about the biology of life from Earth:

• It’s comprised of hydrocarbons, the most important of which are proteins.
• It stores genetic information in long, replicable hydrocarbon chains consisting of diribonucleic acid or DNA.
• Much of it – not all, but a lot – uses oxygen to “burn” ingested food.
• It uses water as a solvent and to transport food, oxygen, and other compounds.

We assume that alien life will follow these rules for the same reason we think sapient aliens will look like humans with funny foreheads. Here’s the problem with that, though:

• Life could be based on elements other than carbon, such as silicon, boron, or sulfur.
• Carbon-based life could use some method to store genetic information besides DNA, or it could reproduce with some method that doesn’t require genetic information.
• It could use other gasses for respiration, like methane or sulfur. Or its metabolism might not require the respiration of gasses.
• It could use other liquids as a solvent, like ammonia. Or it might not need a solvent at all (e.g., artificial intelligence).

And that’s assuming that alien life would even use chemistry as we know it. Robert L. Forward’s novel Dragon’s Egg has life on a neutron star whose biochemistry is mediated by the strong nuclear force instead of the electromagnetic force – in other words, via neutrons and protons instead of electrons. That’s about as alien as you can get.

You can quickly develop analysis paralysis from this, because the possibilities for alien life are so numerous. It helps to put some restrictions on your thinking.

For instance, it turns out that both oxygen and water are abundant in the universe. Oxygen is highly reactive, which is one of the reasons why life on Earth uses it (the Great Oxidation Event being the other). Water is an excellent solvent, and it has a large range of temperatures at which it’s a liquid. Since humans evolved to use both oxygen and water, we can also assume that aliens that use these evolved in environments that humans won’t have too much trouble surviving. Even if our aliens are sapient fish, we can still interact with them via a submarine or SCUBA gear.

Since roleplaying games are all about interaction, we can therefore start putting some bounds on our speculation. Covenant’s aliens (unless they’re artificial intelligences) will breathe oxygen and use water as a solvent, and they’ll do it in environments that humans can easily survive.

I’ll admit that this is just intellectual backfilling to justify the aliens that we already came up with. But it works, so we’ll go with it.

But what about food and medicine?

Even if our aliens are carbon-based, they might not be made up of molecules that we could metabolize, like proteins and carbohydrates. That means we can’t eat their food, use their medicine, or get high on their drugs. At best, a human would vomit up or excrete them. At worst, they would kill a human.

There’s silver linings to this: you probably don’t have worry about catching the alien version of the Black Plague or the clap, and alien predators will probably ignore you, since you don’t smell like food.

However, it complicates a roleplaying game like Covenant:

• Food has to be coded for each species.
• Medicine and drugs could harm or kill an ally from another species.
• Things that many players like to ignore – like keeping track of rations and medicine and, by extension, inventory and encumbrance – become incredibly important.

There’s a reason that many science fiction franchises handwave these issues away. Will Riker can tuck into a plate of delicious wriggly gagh. Dr. McCoy’s job isn’t twice as hard because he has to treat a human ship with a vulcan first officer. Jabba the Hutt can sell “spice” without worrying about who exactly is going to use it.

Covenant, on the other hand, is all about the difficulties in aliens interacting. We want them to be able to interact without too much difficulty, which is why they all breate gaseous oxygen, drink liquid water, and evolved on planets where those two can be found fairly easily. But neither should it be too easy, either.

This extends to social interactions, including love and sex. Tune in tomorrow for more.